🚀 go-pugleaf

On Thu, 22 May 2003 11:33:58 GMT, moby@kcbbs.gen.nz (Mike Diack)
wrote:

>I'm redesigning a device for blind navigation that I first designed a
>decade or so ago, which requires a transformer to drive an
>electrostatic transducer (sweeping 100..50KHz, around 100v P/P driven
>from a 6v P/P source).
>My first iteration used a (hand wound) Philips 10mm 3E25 toroid. I
>gave one of my original samples to a local transformer outfit and
>asked them to make me something smaller (and tidier!)
>Everything they came back with was bigger than my original.
>I have seen a polarisation tranny inside an AKG C460 microphone which
>is smaller than the size of a frozen pea. Admittedly this tranny only
>has to handle a single frequency wheras mine carries a sweep, but who
>can make trannies like that or where can the cores be sourced
>(preferably surface mount)
>cheers
>M


The 100 Hz thing is what hurts. You could use a boost converter to
make 100 VDC at a high switcher frequency (using a very small,
commercial inductor or transformer) and then just power an amp off the
100VDC.

John